The lungs are frequently affected in systemic sclerosis, and pulmonary disease may significantly influence morbidity and mortality. The clinical, radiographic, and physiologic features of scleroderma lung disease are discussed in this article, as are new approaches to the detection and study of interstitial pneumonitis. The pathogenesis of pulmonary fibrosis is discussed in the context of data derived from bronchoalveolar lavage studies. Pulmonary vascular disease and less common pulmonary features of systemic sclerosis are also discussed.